The US did intern German Americans too, in both WW1 and WW2: https://en.wikipedia.org/wiki/Internment_of_German_Americans

About 36% of all people interned in WW2 were Germans. There were far more Germans in the US (millions) so interning them all was totally impractical, unlike the much smaller number of Japanese (~125,000).

In Hawaii about 1/3rd of the population were Japanese. And again, due to the enormous numbers involved, only a small % were interned.

The policies weren't about racism. They were about practicality.